text: Inorganic chemistry has greatly benefited from qualitative theories.  Such theories are easier to learn as they require little background in quantum theory.  Within main group compounds, VSEPR theory powerfully predicts, or at least rationalizes, the structures of main group compounds, such as an explanation for why NH is pyramidal whereas ClF is T-shaped.  For the transition metals, crystal field theory allows one to understand the magnetism of many simple complexes, such as why [[Ferricyanide|[Fe(CN)]]] has only one unpaired electron, whereas [Fe(HO)] has five.  A particularly powerful qualitative approach to assessing the structure and reactivity begins with classifying molecules according to electron counting, focusing on the numbers of valence electrons, usually at the central atom in a molecule.